For Aniello Arena, the star of 'Gomorrah' director Matteo Garrone's new film and a former hit man serving prison time in Italy, acting is 'good for the soul.'

Plenty of actors will say that performing freed them, but Aniello Arena really means it. The star of "Reality," a new film from Italian director Matteo Garrone, Arena is a former mafia hit man 20 years into serving a lifetime prison sentence for murder.

In the movie, which opens in Los Angeles on Friday, Arena plays Luciano, a Neapolitan fishmonger who becomes obsessed with appearing on the Italian version of the reality show "Big Brother." The film won the Grand Prix at last year's Cannes Film Festival, in large part on the strength of its wide-eyed and charismatic leading man; Garrone discovered him after seeing Arena perform a monologue dressed as a clown in a theater troupe at Tuscany's Volterra Detention Center.

A surrealist comedy that darkens as Luciano's delusion grows, "Reality" is about the contagion of yearning as Luciano and his friends and family, including his loving wife, Maria (Loredana Simioli), begin to envision a life of fame and wealth.

"Aniello's face was perfect for this character," Garrone said over a plate of rigatoni at a Beverly Hills restaurant recently. "The eyes are pure. It's about illusion, so you have to be naive. The performance is unique because he combines the talent as an actor with the fact that he stayed for 20 years in jail. You can see in the eyes the surprise of the discovery of a world."

"Reality" is a tonal shift from Garrone's last movie, "Gomorrah," a gritty 2008 drama based on a book about a Neapolitan organized crime syndicate. "Gomorrah," too, won the Grand Prix at Cannes and was an international hit, earning Garrone enough clout in Italy to make "Reality," a more expensive and quirkier movie, this time starring a real-life gangster.

Garrone originally attempted to cast Arena in "Gomorrah," but prison authorities felt the content of the film was not appropriate, Garrone said. Arena, 44, grew up in Naples among the gangs, and was jailed for participating in the murder of three members of a rival clan while in his early 20s. At trial, Arena admitted involvement with organized crime, but said he was innocent of the murders. He has served time in roughly a dozen Italian institutions over the last 20 years, including one in Naples that he described as "a living hell."

"When I first landed in prison in 1993, I wasn't like I am today," Arena said, in an interview via Skype and with the help of a translator, from a cultural center across the street from the Tuscan prison. "I didn't think that much. I was only angry — angry at society, at the entire world."

Like the character he plays in "Reality," Arena is earnest and quick to laugh. Since 1999, he has been a member of Volterra's theater troupe, Compagnia della Fortezza (Theater of the Fortress), a well-regarded company founded by theater director Armando Punzo. Italy has a robust tradition of prison theater, with more than 100 such companies currently operating. Over the years, Arena has played characters as varied as Jiminy Cricket, the antichrist and his personal favorite, drag queens.

"The years pass and you start reflecting on yourself and what you've done," he said. "You start looking at yourself in the mirror. But the real turning point came when I went to Volterra. I started getting immersed in culture.... The experiences I had outside before I was jailed and in the first six or seven years of prison, I didn't believe in human beings, I didn't believe in humanity. But in working on different characters, in trying to flesh them out and in looking at the world through their eyes, I started believing in human beings again."

Though Garrone was unable to cast Arena in "Gomorrah," he didn't forget him. When he decided to make "Reality," which is based on the real-life experience of Garrone's brother-in-law, he wanted all the actors to have what he calls "Pixar faces." Many of Luciano's family members — like Garrone's Naples-born wife's family, he said — have round bodies, moon-shaped faces and vivacious personalities.

"The story of Luciano is the story of many people I know," said Garrone, who grew up in Rome, the son of a theater critic. "They have everything, but they are not satisfied. They follow some desire, some artificial paradise. For me, it was a fairy tale. I wanted it to be very colorful, and the faces to be very expressive."

Arena had already been allowed out of prison on day passes to perform with his theater group, so securing permission to make the movie seemed, to him and to Garrone, a small hurdle. Garrone provided the prison with a detailed shooting schedule, and scouted the nearest jails where Arena would sleep at night.